Gene expression of cytokines, growth factors and apoptosis regulators in a neonatal model of pulmonary stenosis.

Background: Right ventricular remodeling due to pulmonary stenosis increases morbidity in children. Its pathophysiology needs to be clarified. Methods: Six newborn lambs underwent pulmonary arterial banding, seven sham operation. mRNA encoding for cytokines, growth factors and regulators of apoptosis was sequentially measured in myocardium and blood before and up to 12 weeks postoperatively. Results: Experimental animals showed hypertrophy and fibrosis of the right ventricular myocardium, myocardial over-expression of CT-1-mRNA and higher blood concentrations of mRNA encoding for VEGF, TGF-beta, Bak and BcL-xL than controls, respectively. Conclusion: Neonatal pulmonary stenosis leads to myocardial hypertrophy that is associated with CT-1 gene expression and with activation of growth-and apoptosis pathways in blood cells.